title: Postmortem redistribution of tramadol and O-desmethyltramadol.
abstract: Tramadol is a widely used analgesic opioid for moderate-to-severe pain due to its efficacy and safety. Although tramadol induces less adverse effects compared with other opioids, an increased number of documented cases of dependence, abuse, intentional overdose or intoxication have been described. In fatal intoxication, the interpretation of the probable cause of death often relies on the measurement of the tramadol concentration in blood. However, postmortem redistribution (PMR) may affect the results and therefore bias the autopsy report. In the present study, the postmortem cardiac and femoral blood samples from 15 cases of fatal tramadol intoxication were obtained to assess the PMR of tramadol and its main active metabolite, O-desmethyltramadol (M1). Toxicological analysis was performed by the gas chromatography-electron impact-mass spectrometry (GC-EI-MS) method, previously developed and validated for the quantification of both analytes. The cardiac-to-femoral blood ratios of 1.40 and 1.28 were obtained for tramadol and M1, respectively. Results were compared with those in the literature and it was possible to conclude that femoral blood should be considered for quantitative interpretations in fatal cases of tramadol intoxication.
authors.affiliation: 1Department of Sciences, Advanced Institute of Health Sciences-North, CESPU, Cooperativa de Ensino Superior, Politécnico e Universitário, CRL, Central de Gandra Street, 1317, Gandra 4585-116, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Costa
authors.forename: Ana
authors.initials: A
authors.lastname: Oliveira
authors.forename: Paula
authors.initials: P
authors.lastname: Guedes de Pinho
authors.forename: Helena Maria
authors.initials: HM
authors.lastname: Teixeira
authors.forename: Roxana
authors.initials: R
authors.lastname: Moreira
authors.forename: Félix
authors.initials: F
authors.lastname: Carvalho
authors.forename: Ricardo Jorge
authors.initials: RJ
authors.lastname: Dinis-Oliveira
mesh_terms: D000701:Analgesics, Opioid / Q000097:blood / Q000378:metabolism* / Q000506:poisoning; D062787:Drug Overdose; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007202:Indicators and Reagents; D009206:Myocardium / Q000737:chemistry / Q000378:metabolism; D011180:Postmortem Changes; D012015:Reference Standards; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D014018:Tissue Distribution; D014147:Tramadol / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism / Q000506:poisoning
chemical_list: D000701:Analgesics, Opioid; D007202:Indicators and Reagents; C080580:O-demethyltramadol; D014147:Tramadol